Glaucoma is an ophthalmic disease that often manifests as a progressive increase in intraocular pressure. Untreated glaucoma leads to severe defects in the structure of the eye, particularly to damage of the head of the optic nerve, resulting in reduction of the visual field and optical atrophy. In certain instances, the pathology is related to insufficient drainage of aqueous humor from the eye. Other factors, including the production of aqueous humor and pressure on the episcleral veins, may also contribute to development of the condition.